Why
the .20-250?
First, I need to confess that even from the start, I never had any illusions
about the .20-250 being “practical”, or even making much sense on many
levels. Indeed, at the time I was ordering barrel blanks and sending rifle
parts off to Greg Tannel, I knew full well how likely it was that none of
the current mass production bullets were even going to work well for my
specific objectives. But I’m a hot-rodder at heart, and have reached a
point in my hunting/rifle/hand loading hobbies that I’m more interested in
raw pure performance and things that are “unusual” than I am in
“practical”. So, I decided to go ahead with the project, knowing that I was
taking a chance and that it might not work out.

So, how did I decide on the .20-250? A bit of background to put things in
context, might be helpful in understanding how I arrived at the .20-250.
I’ve been using my
.17 Predator
almost exclusively for coyote hunting for a couple of years now. After
having killed over 100 coyotes with the .17P, I am of the opinion that it is
the closest thing to “perfect” for an every stand calling rifle, that I have
ever used. For the ballistics inclined readers, and for reference, my
working load for the .17P has the 30 gr. Gold with a B.C. of .270 doing just
under 4100 fps. You can read all about my .17P project by clicking
here. So,
when I got the itch to begin a new rifle project, I decided that there was
not much point in trying to improve on the .17P for what I call an “every
stand” coyote hunting rifle. Instead I wanted to build an “extreme
performance” rifle. Something that would provide just incredibly flat
trajectory, flatter than any factory made rifle. Trajectory so flat it
would allow me to “hold on fur” all the way out to 400 yards. This would
not be a rifle use on every stand; but rather for more specialized
circumstances, or times when I would be glad to get every ounce of
performance possible. Every ounce of performance possible within certain
parameters, that is! Those “certain parameters” are the initial goals for
what became this .20-250 project. Those goals were:

#1 –
Extreme flatness of trajectory and extended “point blank range”. Even
flatter trajectory and longer point blank range than the .17 Predator. I
wanted something that would shoot flatter and have a longer PBR than any
factory offering. A tall order, given the other goals!

#2 – More downrange energy than the .17 Predator.

#3 – Accomplish #1 and #2, while still keeping recoil low enough to
maintain my site picture in a heavy sporter weight rifle, without a muzzle
brake. This goal effectively ruled out larger calibers and made the project
much more interesting!

#4 – Accomplish #1, #2 & #3, while also providing bang-flop,
dead-right-there terminal performance. As expected, this has proven to be a
function of bullet design and construction and the area that has been most
challenging.

#5 – The rifle had to be a repeater, with slick feeding and no fancy
magazine arrangements or modifications to achieve slick feeding. Hence my
choice of the vanilla ‘250 case, rather than using the BR case or any AI
designs.

#6 – Accomplish all of the above in a barrel no longer than 25”, to
maintain the handling characteristics I prefer in a coyote calling rifle.

Sounds
simple enough, doesn’t it? But, when I started getting down to the nitty
gritty details of accomplishing each of these goals, without making it
impossible to achieve any of the others, the possible options got fewer and
fewer. After some head scratching, talking to lots of other people and
doing a lot of number crunching, I decided that the .20-250 could accomplish
all of my goals simultaneously. So, I decided to give it a try!

I need
to point out one parameter that is conspicuously absent from these goals for
the project and that is barrel life. For this application, I just don’t care
about barrel life. Not even a little bit. This rifle won’t see any prairie
dog shooting, maybe just a little bit of jack rabbit or rock chuck
shooting. But primarily, it’s a predator hunting rifle, and a special
purpose predator hunting rifle at that. If the barrel only lasts 500
rounds, that will equate to many years of service. So, as long as I get 500
rounds out of it, which I’m sure I will, I’m happy. Anything more than that
I’ll take as a bonus.

Another parameter that is conspicuously absent – “fur friendly”. While I
would love to achieve all these goals and be fur friendly too, I just did
not think that is very feasible. So I decided to accept that I’d likely end
up with some big exit holes. While I was willing to accept large holes in
the pelts for this application, I absolutely demand “bang flop” terminal
performance to go along with those large holes. This really comes down to
bullet design and construction. But of course, at the time I was planning
this project, there simply weren’t any .20 caliber bullets available
designed for the kind of velocity and the kind of use I intended. I knew
from the very beginning that finding the right bullet for my application was
probably going to be the biggest challenge on this project. And indeed,
that proved to be true, as I’ll show and describe later.

So, now you know the twisted logic that led this poor inflicted gun nut down
the path to the .20-250. I knew from the outset that I was taking a chance,
and that the project just might end up a failure. Indeed, many of the arm
chair ballistics experts on the internet forums prophesized nothing but
problems ahead for my project. Some of these guys, with no actual
experience to back up their opinions, said I’d wear out the barrel before
finding a good load, that the .20-250 was so grossly overbore that it would
end up barely out performingthe .204 Ruger. I generally tend to ignore
these types on the forums and didn’t take any of their opinions too
seriously. But that didn’t mean I was brimming with confidence, either.
But I took the time to seek out opinions from people that actually do have
real experience for advice. I was able to locate several fellow shooters
who had already built similar large capacity .20 caliber rifles. I gained
valuable insight from each, and for that I am grateful. It turns out that
both of the riflesmiths I contacted about my project have considerable
experience with large capacity .20 calibers as well. Both Greg Tannel, who
I chose to build this rifle, and Kevin Weaver have done a lot of
experimenting with large and extra large capacity .20 calibers. Talking to
these men confirmed nearly all my own thoughts. Namely, that the accuracy
and velocity I wanted to achieve was realistic, that the standard .22-250
case was nearing the limit of useful capacity for the bullet weight range
that I wished to use, and that indeed, finding bullets constructed to
perform the way I wanted them to was likely to present a challenge.